1. Field of the Invention
The present invention relates to an improved One-Piece Connector Assembly which is used to pivotally connect the adjoining end portions of a multiplicity of sucker rods that are angularly disposed relative to one another within a tubing string of like angulation.
2. Description of the Prior Art
Conventional oil well bore holes are dug into the ground from the surface to the location of the pool of oil or producing zone. Typically, such oil well bore holes that extend downwardly from the ground surface to the producing zone are not necessarily straight, but may be crooked, and have a number of dog-leg sections therein. Each of such bore holes has a well head at the surface that supports the tubing string. A polished rod that is reciprocated by conventional power means is connected to the upper end of a multiplicity of sucker rods which form a string that is connected to a reciprocating pump at the bottom of the tubing string. The tubing string has a number of angularly disposed sections therein that conform generally to the dog-leg sections of casing that will frequently be present in the bore hole.
The stationary portion of the reciprocating pump is connected with the lower end of the tubing string. A pull rod extends upwardly from the reciprocating portion of the pump, and the pull rod when reciprocated causes fluid from the producing zone to be discharged upwardly from the pump into the tubing string.
The polished rod is connected by a sequence of rods to the pull rod of the pump. The string of sucker rods are angularly disposed relative to one another. When the string of sucker rods is stressed longitudinally in actuating the pull rod of the pump, the string of sucker rods has been found to be subject to substantial friction.
Attempts have been made to solve this problem by creating a connector assembly which interconnects a pair of adjacent ends of two sucker rods such that the sucker rods can move relative to each other and can be bent at an angle relative to each other, thereby enabling the string of sucker rods to be reciprocated in the tubing string despite the numerous dog-leg bends and further enable the assembly to reduce the numerous longitudinal and lateral forces imparted to it. One such connector assembly is disclosed in U.S. Pat. No. 4,329,124 ("'124 Patent") issued to one of the present Inventors Whetstine B. Pridy. The Invention disclosed in the '124 Patent does work for a period of time but after a few weeks of being subjected to the forces imparted to the strings of sucker rod, the connector assembly described therein broke. Most often, the break occurred along the location of an internal shank identified as number 30 in the '124 Patent. A reason which has been postulated for this breakage was that the connector assembly of the '124 Patent is in two sections which are interconnected by the shank. While this is one reason the connector assembly is able to adjust to various angles and displacements, it also provides a point of weakness where the heavy stresses imparted to the connector assembly are focused.
A significant need therefore exists for an improved connector rod assembly which can interconnect adjacent ends of two sucker rods and which permits the string of rods to be reciprocated with reduced friction through a multiplicity of different dog-log sections in the tubing string.